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[92.242.248.94]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47f85c67339sm53643668f8f.31.2026.07.27.11.12.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jul 2026 11:12:40 -0700 (PDT) From: Jakov Novak To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , David Hildenbrand , Lorenzo Stoakes Cc: Zi Yan , Baolin Wang , "\\ Liam R . Howlett \\ " , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , linux-kernel-mentees@lists.linux.dev, Shuah Khan , Jakov Novak Subject: [PATCH] mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro Date: Mon, 27 Jul 2026 20:11:36 +0200 Message-ID: <20260727181136.2542-1-jakovnovak30@gmail.com> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-kernel-mentees@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Currently, khugepaged locks the khugepaged_mutex in two functions: start_stop_khugepaged and khugepaged_min_free_kbytes_update. Remove mutex_lock/mutex_unlock usage in these functions and replace it with the guard macro. This makes the code more readable (removing a goto statement) and makes it harder to introduce bugs in the future. No functional changes introduced. Signed-off-by: Jakov Novak --- mm/khugepaged.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 617bca76db49..c583867f2e7a 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -3113,7 +3113,7 @@ int start_stop_khugepaged(void) { int err = 0; - mutex_lock(&khugepaged_mutex); + guard(mutex)(&khugepaged_mutex); if (hugepage_enabled()) { if (!khugepaged_thread) khugepaged_thread = kthread_run(khugepaged, NULL, @@ -3122,7 +3122,7 @@ int start_stop_khugepaged(void) pr_err("khugepaged: kthread_run(khugepaged) failed\n"); err = PTR_ERR(khugepaged_thread); khugepaged_thread = NULL; - goto fail; + return err; } if (!list_empty(&khugepaged_scan.mm_head)) @@ -3132,17 +3132,14 @@ int start_stop_khugepaged(void) khugepaged_thread = NULL; } set_recommended_min_free_kbytes(); -fail: - mutex_unlock(&khugepaged_mutex); return err; } void khugepaged_min_free_kbytes_update(void) { - mutex_lock(&khugepaged_mutex); + guard(mutex)(&khugepaged_mutex); if (hugepage_enabled() && khugepaged_thread) set_recommended_min_free_kbytes(); - mutex_unlock(&khugepaged_mutex); } bool current_is_khugepaged(void) -- 2.55.0